The present invention is generally related to radios, and more specifically related to software-defined radios. The desire to increase functionality and programmability in radio systems has lead to the evolution of software radios. Software radios implement selected functions in software that have typically been implemented in hardware. Software radios provide a higher degree of flexibility than hardware radios. Typically, radios are classified as hardware radios, software-based radios, or software-defined radios. Software radios include less hardware and more software than hardware radios, but remain operationally constrained by the hardware present. Software-defined radios include less hardware than software radios and more software than software-based radios, and often can change complete functions or modulation characteristics by adding, changing or updating software. Thus, software-defined radios typically provide the most flexibility and programmability of these three types of radios.
Software-defined radios can take a relatively long time (compared to hardware radios and software-based radios) to become fully operational from a powered-down state. The time needed for the software-defined radio to become fully functional after power is turned on can become longer as more (and more complex) software functions are added to the software-defined radio. This is analogous to adding software to a desktop computer. As the amount of software increases and the complexity of the software increases, the time needed to turn the computer on increases.
The amount of time needed to turn on a software-defined radio is of particular concern in military applications. For example, a military hand held radio may be implemented as a software-defined radio. Military hand held radios are often used in the field for long periods of time operating on battery power. Thus, it is not uncommon for an operator to turn the radio off to conserve power and prolong battery life. Under some conditions, it is desired that the military radio be able to be turned on as quickly as possible, and lengthy power on times can not be tolerated. An example of such a condition is when an operator of a military hand held radio is under attack. While under attack, the operator may desire to turn the radio on and transmit a signal indicating his location and the fact that he needs help. Under such conditions, long power-on times may cost the operator his life. A technique for decreasing the amount of time needed to turn on a software-defined radio is desired.
In one embodiment, a method for decreasing power-on time of a software-defined radio comprising a hardware portion, an application portion, and an operating environment portion includes removing electrical power from at least one hardware component of the hardware portion in response to a power-off signal. The application portion is configured to be in an application-portion suspended state in response to the power-off signal, wherein selected application parameters are retained in the application portion. The operating environment is configured to be in an operating-environment-suspended state in response to the power-off signal, wherein selected operating environment parameters are retained in the operating environment portion. Power is restored to at least one hardware component of the hardware portion in response to a power-on signal. The application portion, is restored to an application-portion-operational state utilizing the retained selected application portion parameters in response to the power-on signal. The operating environment portion is restored to an operating-environment-portion operational state utilizing the retained selected operating environment parameters in response to the power-on signal.
In another embodiment a system for decreasing power-on time of a software-defined radio includes a power control portion, a fast-on control portion, an application portion, an operating environment portion, and a hardware portion. The power control portion is configured to receive a selected power status of the software-defined radio and either provide power to selected portions of the software-defined radio or remove power from selected portions of the software-defined radio in response to the selected power status. The fast-on control portion is configured to configure selected portions of the software-defined radio to be in either a suspended state or an operational state in response to the selected power status. The application portion includes radio-related applications, wherein selected radio-related applications are configured to be in either a suspended state or an operational state responsive to the selected power status. The operating environment portion includes radio-related software portions, wherein selected radio-related software portions are configured to be in either a suspended state or an operational state responsive to the selected power status. The hardware portion includes hardware components, wherein power to selected hardware components is either provided and removed in response to the selected power status.